He’s “Butterfingers” Biden. The president accidentally dropped and then had to chase a challenge coin as it rolled away from him Monday during an awkward exchange with a senior military officer. The oldest-ever president had to bend down to retrieve the coin after a failed handoff with US Air Force Col. Ethan P. Hinkins, whom Biden greeted before meeting with a group of Minnesota lawmakers at Minneapolis-Saint Paul International Airport. Biden has given out several presidential coins during his administration, including to Pope Francis and Ukrainian President Volodymyr Zelensky. “I know my son would want me to give this to...